feat(epp): add role-scoped worker catalogs for standalone disaggregated routing

[kangclzjc]

Summary

Closes #13406 (DEP #11661, Milestone 5). With
DYN_EPP_TOPOLOGY_MODE=disaggregated, the standalone Rust EPP splits the pods selected by one
InferencePool into prefill and decode catalogs using a configurable worker-role label, and drives
two independent embedded SelectionService instances from them.

Two instances, not one instance with two routing groups. use_kv_events is fixed when a
SelectionService is built and differs per role, and the two catalogs must be disjoint so a decode
pick can never see a prefill worker. Everything else that separates the roles is per-request: the
decode selector carries the same RouterConfigOverride the Dynamo-runtime EPP applies to its decode
leg (decode_router_config_override, shared from epp.rs) and supplies it on every selection and
booking; prefill and aggregated carry none.

	prefill	decode
static use_kv_events	base	false
static router_predicted_ttl_secs	base	cleared (needs events)
per-request RouterConfigOverride	none	overlap_score_credit: 0.0, assume_kv_reuse: false, track_prefill_tokens: false

Prefill scores prefix overlap and does not model long-lived block occupancy; decode ignores overlap
and does model occupancy. A decode worker did not compute the prompt, so charging it prefill work
would mis-rank it, and crediting it for a prefix it never cached would be a fiction. Decode workers
therefore carry no kv_events_endpoint and no replay_endpoint, which is exactly what makes them
Schedulable under use_kv_events=false.

Prefill is a selection input only. All five reflector reads on the request path are scoped to the
serving role, and an empty decode catalog returns the new PickError::RoleCatalogEmpty (503)
instead of falling back to a prefill endpoint. build_request_header_response is the sole producer
of x-gateway-destination-endpoint and is reachable only through pick(), so scoping pick()
scopes the whole surface.

Aggregated mode is unchanged. The role label is never read, one catalog is built, and the
existing single-selector path runs byte-identically.

Requirement-by-requirement

#	Issue requirement	Where
1	Topology configuration + worker-role label contract	epp_standalone_config.rs — EppTopologyMode, DYN_EPP_WORKER_ROLE_LABEL (default nvidia.com/dynamo-worker-role), label-key syntax validation
2	Split eligible pool pods into prefill/decode sets	pod_discovery.rs — raw_worker_from_pod resolves the role after the existing eligibility gates
3	Role-scoped catalogs, KV-event inputs, readiness, selector config	pod_discovery.rs (IndexState/RoleCounts), role_config.rs, selector.rs, topology_adapter.rs
4	Prefill never selected as a destination	epp_router.rs serving_role, picker.rs RoleCatalogEmpty, server.rs 503 mapping
5	Unit + integration coverage	18 net new test functions over main (table-style; 161 in the crate) across role changes, missing/invalid labels, add/remove reconciliation, and the routing invariant

New environment variables

DYN_EPP_TOPOLOGY_MODE, DYN_EPP_WORKER_ROLE_LABEL, and two per-role capacity overrides
(DYN_EPP_{PREFILL,DECODE}_MAX_NUM_BATCHED_TOKENS) that fall back to the shared value. Real P/D
fleets differ by 8–16× here, and max_num_batched_tokens is the denominator of
PolicyClassConfig::worker_is_busy. Per-role KV-block totals are deliberately not added: nothing in
this split consumes distinct totals yet.

Two configurations are rejected at startup rather than silently reinterpreted: DYN_EPP_PEER_SERVICE
with disaggregated (both instances would bind the one hardcoded replica-agg port; Milestone 8 /
#13418 owns multi-replica disagg), and DYN_ROUTER_CONDITIONAL_DISAGG (it requires decode-side KV
events and bypass orchestration SelectionService does not perform).
DYN_EPP_TOPOLOGY_MODE is standalone-only configuration like its siblings; the Dynamo-runtime mode
ignores it.

DEP #11661 corrections this surfaced

• The two per-role max_num_batched_tokens env vars are missing from the Environment Contract.
• The role label key is now nvidia.com/dynamo-worker-role; the DEP says nvidia.com/role in four places.
• DYN_EPP_KV_EVENT_PORT / DYN_EPP_KV_EVENT_REPLAY_PORT apply to prefill only under disaggregated.
• Decode workers have no kv_events_endpoints and no replay_endpoint.
• DYN_EPP_WORKER_ROLE_LABEL is optional-with-default, not "Conditional" required.
• Conditional disaggregation is rejected by the standalone EPP; the DEP marks it "Needs design".

Deliberately not in this change

Owned by the sibling issues: prefill/decode pair selection and reservation (#13407), the
decode-sidecar request contract (#13405), NIXL handoff (#13404), and manifests / e2e / benchmarking
(#13408). Per-role policy and queue configuration is recorded against #13407; metrics are
Milestone 9. Until #13405 and #13407 land the prefill catalog is populated but nothing selects from
it, so the EPP logs that at startup and the docs carry the same note.

Validation

• cargo fmt -p dynamo-ext-proc -- --check
• cargo clippy -p dynamo-ext-proc --all-targets -- -D warnings
• cargo test -p dynamo-ext-proc — 161 passed, 0 failed
• Focused areas: worker role (9), per-role router config (10), standalone config (18 new), pod
  discovery (14 new), topology adapter (3 new), plus the existing aggregated suite unchanged

============

Kubernetes Validation Summary

Revision 1 run. The revision-2 rerun (new label key, override refactor, guard removal) is in the
follow-up comment below.

Tested on a real Kubernetes cluster — throwaway k3s v1.34.2 in Docker, Gateway API v1.5.1 + GAIE
CRDs v1.2.1 + agentgateway v1.0.0 — installed with this repo's own documented procedure,
deploy/inference-gateway/scripts/install_gaie_crd_agentgateway.sh per
Install Gateway API Inference Extension.

GPU-less setup: the workers are traefik/whoami echo servers carrying the nvidia.com/role label,
and the EPP runs off-cluster against the same API server with a stub standing in for vLLM's
/v1/chat/completions/render. Everything the gateway itself touches — InferencePool, HTTPRoute,
the EPP Service — is exactly what deploy/inference-gateway/ext-proc/examples/onramp/agg.yaml
ships. Echo workers are enough here because this issue is about which endpoint the EPP hands the
gateway, not about what the endpoint computes.

• Role split from one InferencePool — 2 prefill + 2 decode pods, two SelectionService
  instances, two policy classes, independent readiness per role.
• KV events are prefill-only — ZMQ listeners start for the prefill pod IPs and no others, and
  follow the label across role changes.
• The gateway never receives a prefill endpoint — 100/100 requests landed on decode-role pods,
  cross-checked against each pod's live label.
• Empty decode catalog fails closed — 503 no decode workers available instead of falling back
  to a prefill endpoint.
• Live role changes reconcile — flips in both directions, label removal, and an unparseable
  label value, each with an attributable log line.
• Aggregated mode is unchanged — same pool, same labels, one catalog, all pods serving.

Step 1: install the gateway with the documented script

$ NAMESPACE=epp-disagg AGW_NAMESPACE=agentgateway-system \
    ./deploy/inference-gateway/scripts/install_gaie_crd_agentgateway.sh
...
agentgatewayparameters.agentgateway.dev/inference-gateway-params serverside-applied
gateway.gateway.networking.k8s.io/inference-gateway created
gateway.gateway.networking.k8s.io/inference-gateway condition met

$ kubectl get gatewayclass
NAME           CONTROLLER                      ACCEPTED   AGE
agentgateway   agentgateway.dev/agentgateway   True       12s

$ kubectl get gateway inference-gateway -n agentgateway-system
NAME                CLASS          ADDRESS   PROGRAMMED   AGE
inference-gateway   agentgateway             True         10s

Step 2: apply the disaggregated workload

$ kubectl -n epp-disagg get pods -o custom-columns='NAME:.metadata.name,IP:.status.podIP,ROLE:.metadata.labels.nvidia\.com/role,READY:...'
NAME                            IP          ROLE      READY
vllm-decode-944754ff7-f87cw     10.42.0.9   decode    True
vllm-decode-944754ff7-pnsls     10.42.0.8   decode    True
vllm-prefill-68cb66cf4d-kxwbl   10.42.0.7   prefill   True
vllm-prefill-68cb66cf4d-ljtnm   10.42.0.6   prefill   True

$ kubectl -n epp-disagg get httproute vllm-qwen-route -o jsonpath=...
agentgateway.dev/agentgateway Accepted=True ResolvedRefs=True

Step 3: EPP startup — two catalogs, and ZMQ only for prefill 🔥

Prefill pods are 10.42.0.6 and 10.42.0.7; decode pods are 10.42.0.8 and 10.42.0.9. Only the
prefill pair gets a KV-event subscription, which is the whole point of use_kv_events=false and
kv_events_endpoint: None on the decode role.

INFO dynamo_ext_proc::runner: Listening for ext_proc connections (TLS) addr=0.0.0.0:9002
INFO dynamo_ext_proc::pod_discovery: Role has ready workers role="prefill" ready=2
INFO dynamo_ext_proc::pod_discovery: Role has ready workers role="decode" ready=2
INFO ...indexer::listener: ZMQ listener starting worker_id=6967477426482853 endpoint="tcp://10.42.0.6:5557"
INFO ...indexer::listener: ZMQ listener starting worker_id=1819057378898784 endpoint="tcp://10.42.0.7:5557"
WARN dynamo_ext_proc::epp_router: DYN_EPP_TOPOLOGY_MODE=disaggregated is incomplete until
     ai-dynamo/dynamo#13405 and #13407 land: the prefill catalog is populated but nothing selects
     from it yet, so decode workers still perform the whole prefill

Step 4: end-to-end request through the gateway

The echo worker reflects the headers it received, so the EPP's decision is visible in the response
body itself.

$ curl -i http://<gateway>/v1/chat/completions -H 'content-type: application/json' \
    -d '{"model":"Qwen/Qwen3-0.6B","messages":[{"role":"user","content":"hello world from the gateway"}]}'
HTTP/1.1 200 OK

Hostname: vllm-decode-944754ff7-pnsls
IP: 10.42.0.8
RemoteAddr: 10.42.0.5:54164
POST /v1/chat/completions HTTP/1.1
X-Gateway-Destination-Endpoint: 10.42.0.8:8000

Step 5: 100 requests, destinations cross-checked against live role labels 🔥

Run after several role flips, so two pods carry a name from the opposite Deployment. Routing follows
the label, not the name — which is what the issue asks for.

$ kubectl -n epp-disagg get pods -o custom-columns='NAME,IP,ROLE'
vllm-prefill-68cb66cf4d-kxwbl   10.42.0.7    decode
vllm-decode-944754ff7-qv4p5     10.42.0.12   decode
vllm-decode-944754ff7-zvlzm     10.42.0.13   decode
vllm-prefill-68cb66cf4d-ljtnm   10.42.0.6    prefill
vllm-decode-944754ff7-nx6hq     10.42.0.11   prefill
vllm-prefill-68cb66cf4d-rk75z   10.42.0.10   prefill

$ # 100 requests; tally X-Gateway-Destination-Endpoint against the live label
40 requests -> 10.42.0.12 role=decode
31 requests -> 10.42.0.13 role=decode
29 requests -> 10.42.0.7 role=decode

0 of 100 reached a prefill-role pod. Same result on the earlier 60-request runs.

Step 6: drain decode, prefill still Ready

The decode pods are confirmed gone from the API server, not merely terminating, and the pool still
holds two eligible Ready prefill pods — so this is an empty role catalog, not an empty pool.

$ kubectl -n epp-disagg scale deploy/vllm-decode --replicas=0
$ kubectl -n epp-disagg wait --for=delete pod -l nvidia.com/role=decode --timeout=90s
pod/vllm-decode-944754ff7-f87cw condition met
pod/vllm-decode-944754ff7-pnsls condition met

$ kubectl -n epp-disagg get pods
vllm-prefill-68cb66cf4d-kxwbl   prefill   Running
vllm-prefill-68cb66cf4d-ljtnm   prefill   Running

$ curl -i http://<gateway>/v1/chat/completions -d '{...}'
HTTP/1.1 503 Service Unavailable
content-length: 27

no decode workers available

The EPP confirms the same thing independently: both decode workers are removed from the decode
selector, and the request that follows produces no Selected worker and no Request routed
line — pick() short-circuits on has_ready_workers(Decode) before it ever reaches the selector,
which is exactly PickError::RoleCatalogEmpty(Decode).

06:09:34.352529 WARN ...sequences::multi_worker: Removing worker WorkerWithDpRank { worker_id: 4220446411653535 }  # 10.42.0.8
06:09:34.353019 WARN ...pod_discovery: Role has no ready workers; requests needing it will fail
                     until one appears role="decode"
06:09:34.353328 WARN ...sequences::multi_worker: Removing worker WorkerWithDpRank { worker_id: 6957111713067280 }  # 10.42.0.9

06:09:38.028162 DEBUG ...server: Received RequestHeaders from Envoy
06:09:38.028270 DEBUG ...server: Received RequestBody from Envoy body_len=83
06:09:38.028292 DEBUG ...server: Received RequestBody from Envoy eos=true
                       # no Selected worker, no Request routed -- compare Step 4

Deleting the pods leaves one confound: it does not separate "the decode catalog is empty" from "the
pod is not there". Step 8's label removal closes that — the pod stays Running, Ready and
pool-selected, and only its role label goes away, reaching the identical 503 through a completely
different path.

Fails closed with an attributable body, rather than falling back to a prefill endpoint.

Step 7: live role changes

prefill → decode: the pod moves catalogs in place, starts serving immediately, and its KV-event
subscription is torn down.

$ kubectl -n epp-disagg label pod vllm-prefill-68cb66cf4d-kxwbl nvidia.com/role=decode --overwrite
Hostname: vllm-prefill-68cb66cf4d-kxwbl      # x3, it is now the only decode worker

INFO ...indexer::listener: ZMQ listener exiting after cancellation self.worker_id=1819057378898784

decode → prefill: the pod stops receiving traffic and gains a subscription.

$ kubectl -n epp-disagg label pod vllm-decode-944754ff7-nx6hq nvidia.com/role=prefill --overwrite
$ # 30 requests
     11 vllm-decode-944754ff7-zvlzm
     10 vllm-decode-944754ff7-qv4p5
      9 vllm-prefill-68cb66cf4d-kxwbl     # nx6hq: 0

INFO ...indexer::listener: ZMQ listener starting worker_id=8935336512433373 endpoint="tcp://10.42.0.11:5557"

Step 8: missing and invalid role labels

$ kubectl label pod ... nvidia.com/role-                       -> 503 no decode workers available
$ kubectl label pod ... nvidia.com/role=encode --overwrite     -> 503 no decode workers available
$ kubectl label pod ... nvidia.com/role=decode --overwrite     -> 200

WARN ...pod_discovery: Pod is pool-selected and Ready but has no usable worker role; excluding it
     pod="vllm-prefill-68cb66cf4d-kxwbl" reason="role_label_missing" error=role label is missing
WARN ...pod_discovery: Pod is pool-selected and Ready but has no usable worker role; excluding it
     pod="vllm-prefill-68cb66cf4d-kxwbl" reason="role_label_invalid"
     error=role label value "encode" names no worker role

Startup never fails on this — a rolling update transiently produces such pods.

Step 9: a client cannot force a prefill endpoint

In GAIE the EPP answers the gateway with an x-gateway-destination-endpoint header and the gateway
forwards there. So the cheapest way to defeat requirement #4 needs no bug in the catalog logic at
all: the client sets that header itself and names a prefill pod. envoy_helpers.rs:54-58 argues
this cannot work — the header is deliberately kept out of STRIPPED_REQUEST_HEADERS because the EPP
writes it with OverwriteIfExistsOrAdd, which already replaces any client value, and stripping it
as well would make the outcome depend on Envoy's set-vs-remove ordering. This step checks that
argument against a real gateway.

Each row is one curl carrying a forged header. Pod names are unreliable after Step 7's flips, so
both role columns are the live label, which is what actually decides.

forged header the client sent	role of that pod	endpoint the EPP returned	pod that served the request	role of that pod
10.42.0.6:8000	prefill	10.42.0.11:8000	vllm-decode-944754ff7-nx6hq	decode
10.42.0.10:8000	prefill	10.42.0.7:8000	vllm-prefill-68cb66cf4d-kxwbl	decode

The two role columns are the test's precondition and its assertion:

• Column 2 must be prefill. Forging a decode IP would prove nothing — override and no-override
  produce the same landing pod, so the test would have no discriminating power.
• Column 5 must be decode. That is the pass condition. Had the spoof worked, the response
  would have come from vllm-prefill-…-ljtnm or vllm-prefill-…-rk75z, the two pods actually
  labelled prefill at that moment.

Row 2 is why names cannot be trusted: vllm-prefill-…-kxwbl reads like a prefill pod but was
flipped to decode in Step 7, and the Deployment name never changed.

06:11:24.061149 INFO ...selector: Selected worker worker_id=8935336512433373
06:11:24.061409 INFO ...server: Request routed endpoint=10.42.0.11:8000
06:11:24.061449 DEBUG ...envoy_helpers: [FINAL-MUTATION] set_headers
                key=x-gateway-destination-endpoint value=10.42.0.11:8000 append_action=2

06:11:24.109389 INFO ...selector: Selected worker worker_id=1819057378898784
06:11:24.109524 INFO ...server: Request routed endpoint=10.42.0.7:8000
06:11:24.109550 DEBUG ...envoy_helpers: [FINAL-MUTATION] set_headers
                key=x-gateway-destination-endpoint value=10.42.0.7:8000 append_action=2

append_action=2 is OverwriteIfExistsOrAdd. What this run establishes is the end-to-end property
— a client-supplied value does not change the destination. It does not distinguish whether the
forged header was dropped before ext_proc or overwritten after it, and it does not need to.

Step 10: aggregated parity, same cluster and same labels

Restart the EPP with DYN_EPP_TOPOLOGY_MODE unset against the identical pool. The role label is
never read, all 6 pods form one catalog, all 6 get KV-event listeners, all 6 serve.

INFO dynamo_ext_proc::pod_discovery: Role has ready workers role="aggregated" ready=6
INFO ...indexer::listener: ZMQ listener starting endpoint="tcp://10.42.0.6:5557"
INFO ...indexer::listener: ZMQ listener starting endpoint="tcp://10.42.0.7:5557"
INFO ...indexer::listener: ZMQ listener starting endpoint="tcp://10.42.0.10:5557"
INFO ...indexer::listener: ZMQ listener starting endpoint="tcp://10.42.0.11:5557"
INFO ...indexer::listener: ZMQ listener starting endpoint="tcp://10.42.0.12:5557"
INFO ...indexer::listener: ZMQ listener starting endpoint="tcp://10.42.0.13:5557"

$ # 60 requests
     14 vllm-prefill-68cb66cf4d-kxwbl
     14 vllm-decode-944754ff7-zvlzm
     12 vllm-decode-944754ff7-qv4p5
      8 vllm-prefill-68cb66cf4d-ljtnm
      8 vllm-decode-944754ff7-nx6hq
      4 vllm-prefill-68cb66cf4d-rk75z

Not covered by this run

Real vLLM workers, real KV-cache events (the ZMQ sockets connect but no worker publishes), NIXL
transfer, and prefill/decode pairing — pairing is #13407 and is what makes the prefill catalog do
anything, so it cannot be exercised until that lands. Multi-replica EPP under disaggregated is
rejected at startup and is Milestone 8 (#13418).

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Walkthrough

Standalone EPP now supports aggregated and disaggregated topologies. It classifies workers by role, maintains separate prefill and decode catalogs, applies role-specific capacities and routing, rejects unsupported runtime combinations, and documents current limitations.

Changes

Standalone disaggregated EPP

Layer / File(s)	Summary
Role contracts and configuration deploy/inference-gateway/ext-proc/src/worker_role.rs, deploy/inference-gateway/ext-proc/src/epp_standalone_config.rs, deploy/inference-gateway/ext-proc/src/role_config.rs, deploy/inference-gateway/ext-proc/src/runner.rs, deploy/inference-gateway/ext-proc/src/lib.rs	Adds worker-role types, topology parsing, role-specific capacity settings, role-aware KV-router profiles, label validation, crate exports, and Dynamo-runtime validation.
Role-aware pod discovery deploy/inference-gateway/ext-proc/src/pod_discovery.rs	Classifies eligible pods as prefill or decode workers, tracks per-role counts, exposes role-scoped queries, evicts invalid workers, and omits KV/replay endpoints for decode workers.
Role selectors and request routing deploy/inference-gateway/ext-proc/src/selector.rs, deploy/inference-gateway/ext-proc/src/epp_router.rs, deploy/inference-gateway/ext-proc/src/picker.rs, deploy/inference-gateway/ext-proc/src/server.rs	Creates separate selectors, restricts selection and endpoint resolution to the active role, adds role-specific empty-catalog errors, and maps those errors to HTTP 503 responses.
Role reconciliation and operator guidance deploy/inference-gateway/ext-proc/src/topology_adapter.rs, deploy/inference-gateway/ext-proc/examples/onramp/README.md, docs/fern/pages/kubernetes/kv-aware-routing/vanilla-vllm-onramp.mdx	Reconciles role-specific catalogs and capacities, supports decode registrations without KV endpoints, and documents configuration requirements and current pairing limitations.

Estimated code review effort: 4 (Complex) | ~60 minutes

Merge Risk: 🟡 Moderate · up to 15f18

Some valid router configurations may prevent the standalone EPP from starting because decode-specific settings are not fully adjusted for its routing model. This is a concrete startup-readiness risk that should be fixed or explicitly rejected before merge.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

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Description check	✅ Passed	The description is detailed and covers the overview, implementation details, validation results, scope boundaries, and linked issue #13406. It does not use every template heading, but it provides th…
Title check	✅ Passed	The title clearly and concisely describes the main change: adding role-scoped worker catalogs for standalone disaggregated EPP routing.

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The description is detailed and covers the overview, implementation details, validation results, scope boundaries, and linked issue #13406. It does not use every template heading, but it provides the required information in equivalent sections.

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Inline comments:
In `@deploy/inference-gateway/ext-proc/src/role_config.rs`:
- Around line 109-126: The WorkerRole::Decode arm must also clear or reject the
incompatible router_prefill_load_model and serve_indexer settings before
SelectionServiceBuilder::build validates the configuration. Keep decode’s
existing router_track_prefill_tokens=false and overlap_score_credit=0.0 behavior
consistent with those adjustments, while leaving router_assume_kv_reuse
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• deploy/inference-gateway/ext-proc/examples/onramp/README.md
• deploy/inference-gateway/ext-proc/src/epp_router.rs
• deploy/inference-gateway/ext-proc/src/epp_standalone_config.rs
• deploy/inference-gateway/ext-proc/src/lib.rs
• deploy/inference-gateway/ext-proc/src/picker.rs
• deploy/inference-gateway/ext-proc/src/pod_discovery.rs
• deploy/inference-gateway/ext-proc/src/role_config.rs
• deploy/inference-gateway/ext-proc/src/runner.rs
• deploy/inference-gateway/ext-proc/src/selector.rs
• deploy/inference-gateway/ext-proc/src/server.rs
• deploy/inference-gateway/ext-proc/src/topology_adapter.rs
• deploy/inference-gateway/ext-proc/src/worker_role.rs
• docs/fern/pages/kubernetes/kv-aware-routing/vanilla-vllm-onramp.mdx

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[dynamo-ops]

/ok to test 339d297

[dynamo-ops]

/ok to test 8134b71

[kangclzjc]

Follow-up from a multi-agent review of this PR — 3 fixes, re-verified on a real cluster

Ran a six-lens adversarial review over the diff (each finding then handed to a verifier whose job
was to refute it). 13 raw findings, 9 survived dedupe into verification, all 9 refuted. Three
that the verifiers dismissed turned out to be real on a closer read, and they are fixed in
8134b71.

The load-bearing conclusion held up, and in a stronger form than "the code is correct": every
reflector read filters on strict role equality (pod_discovery.rs:352, :367, :387) and
WorkerRole::Aggregated is not a wildcard, so a mistake in the role plumbing fails closed with a
503 rather than leaking a prefill endpoint.

1. A role that is empty from process start was reported by nothing

log_role_count_transitions only fires on a crossed-zero edge, and last_counts starts at zeros
(pod_discovery.rs:205), so a role that was never populated never crosses. The likeliest
misconfiguration this topology makes possible — the role label misspelled on every decode pod —
logged a healthy prefill line and said nothing at all about decode, leaving the 503s as the only
signal. Worse, an all-empty index does not even set index_changed, so both roles were silent.

That contradicted the function's own doc comment, which claims the log line is the signal for
exactly this condition since health stays SERVING by design.

Fixed by reporting a full census the first time discovery holds a complete picture, then
transitions as before.

Before and after, same cluster, same state (2 prefill / 0 decode, decode deleted before the EPP
started):

# before
INFO  pod_discovery: Role has ready workers role="prefill" ready=2
# ...and nothing else. Decode is not mentioned.

# after
INFO  pod_discovery: Role has ready workers role="prefill" ready=2
WARN  pod_discovery: Role has no ready workers at startup; requests needing it will fail
      until one appears. Check the worker-role label on this pool's pods.

The <details> below has the rest of the matrix.

Startup-census verification matrix (real k3s + agentgateway, same setup as the PR body)

case	expected	observed
disagg, 2 prefill / 0 decode before EPP start	prefill info + decode warn	✅ both, as quoted above
disagg, pool entirely empty (index_changed never set)	both roles warn	✅ role="prefill" and role="decode", one warn each
disagg, healthy 2 + 2	one line per role, no duplicate with the transition log	✅ exactly two INFO lines
aggregated, same pool and labels	census silent; startup output unchanged	✅ role="aggregated" ready=4, zero at startup lines
routing invariant re-check after touching the reflector loop	100% decode	✅ 90/90 requests over two runs to decode-role pods, 0 to prefill
empty-pool request	503	✅ no decode workers available

A regression I introduced and caught here: the first version of this fix silently swallowed the
pre-existing aggregated startup line Role has ready workers role="aggregated" ready=N, because the
census branch is a no-op under aggregated yet still advanced last_counts. The aggregated-parity
row above is what caught it. first_census is now gated on the role label as well as on readiness,
so under aggregated the block collapses to exactly the transition-only path it had before.

2 & 3. Two wrong rows in the config table

-| `DYN_EPP_WORKER_ROLE_LABEL` | With `disaggregated` | ... defaults to `nvidia.com/role`. ... |
+| `DYN_EPP_WORKER_ROLE_LABEL` | No | ... defaults to `nvidia.com/role`. Read only under
+  `disaggregated`, where every pool pod must carry it ... |

The Required column contradicted its own row: the variable has a default. (This PR's description
lists "DYN_EPP_WORKER_ROLE_LABEL is optional-with-default, not 'Conditional' required" as a DEP
#11661 correction — and then reproduced the same error in its own table.)

DYN_EPP_SELECTION_INDEXER_THREADS was documented as "defaults to 4" with no qualification, but
under disaggregated the decode selector ignores it entirely and is pinned to one thread
(selector.rs:172-175), because its index is never fed. The row now says so.

Findings I judged not actionable

• The <Note> does not say that KV-aware selection is off for served traffic under
  disaggregated. Mechanically true — serving() is the decode selector, which runs with
  overlap_score_credit=0.0. But decode being load-only is the permanent target design
  (role_config.rs:12-24), not a gap that feat(epp): add a decode-sidecar request contract for standalone disaggregated routing #13405/feat(epp): add paired prefill/decode selection and reservation lifecycle #13407 close, so folding it into a "does not yet
  … lands with" note would be inaccurate. The page already scopes disaggregated as not-yet-serving
  in four places.
• RoleSelectors::serving() has no direct test. Real, but a swapped arm fails closed
  (serving_role still scopes the reflector reads, so the endpoint would not resolve) rather than
  leaking. Left for feat(epp): add paired prefill/decode selection and reservation lifecycle #13407, which changes this code anyway.

Status

cargo test -p dynamo-ext-proc: 181 passed (178 before; +3 pin the census against
never-populated, all-empty, and aggregated-silent). clippy -D warnings and fmt clean.

🤖 Generated with Claude Code

[dagil-nvidia]

Approving on content at head 8134b71: all five deterministic gates pass with proof (CODEOWNERS drift 0 at 605 rules, 5501/5501 files owned, 93 matcher tests, 18 skills, docs linter proven with injected-H1 and stripped-SPDX probes), and rust-tests (.) plus clippy are green on this exact head with the changed crate in the workspace. The docs slice matches the new config surface exactly - all six env vars, defaults, per-role fallbacks, the decode indexer-thread pin, and the troubleshooting claim that startup errors name the role-specific variable. The core invariant (a prefill worker can never become a routing destination) is scoped at every request-path read, enforced by strict role equality in endpoint resolution, and pinned by tests at three levels. The one coderabbit thread is fixed at head.

Merge logistics: the red dynamo-runtime / test jobs and the gating status check are unrelated to this PR - a broken self-hosted runner bootstrap plus profiler integration tests in files this PR does not touch, which pass on newer runs of other PRs. A rerun or rebase clears them; nothing here needs fixing for that.

Three non-blocking notes:

1. vanilla-vllm-onramp.mdx:501 - the DYN_EPP_KV_EVENT_PORT and DYN_EPP_KV_EVENT_REPLAY_PORT rows are the only config rows whose disaggregated behavior changed without gaining a disaggregated qualifier (per the PR body's own corrections list, both apply to prefill only; decode workers consume no KV events). Append that clause to both rows like their siblings.
2. pod_discovery.rs:293,469,838 - comments claim aggregated startup output stays "byte-identical", but that holds only against this PR's first commit; against the merge base, aggregated mode now emits new role-transition log lines. The lines are harmless - reword the comments to claim only that the census adds nothing under aggregated, or gate transitions on role_label.is_some() if literal parity is the intent.
3. selector.rs:448 - schedulable_count is a non-test pub fn whose only callers are test code; either document it as intentional observability API for custom-EPP builders or gate it #[cfg(test)] beside its sibling.

Automated review pass; severity escalation stays with the human reviewers.

[tmonty12]

Thanks for splitting the catalogs by role. Before the next revision:

• Please rebase onto current main; GitHub currently reports this PR as having conflicts.
• Trim the comments substantially. The module docs and many inline/method comments restate implementation detail or defend every branch. Keep short comments for non-obvious invariants and rationale.
• Consolidate the new tests around the existing helpers/table tests. Keep the role partition/routing behavior and the important configuration validation/fallback cases, but avoid one-test-per-parser/accessor/helper coverage.

The inline comments cover the configuration and behavior changes I think we need.

[tmonty12]

Please reduce this to a one-sentence module doc. The configuration matrix and prose restate implementation details and will drift once the decode selection policy moves into RouterConfigOverride; retain only the non-obvious invariant.

[kangclzjc]

Done in d9ba8e1 / d169155. The module doc is now one sentence — the invariant the code cannot state (a decode worker never computed the prompt, so it is never credited for overlap or charged prefill work; it has no event source). The "why two services" rationale lives once, at build_selectors, and says what stays true after the override move: use_kv_events is fixed at construction and the catalogs must be disjoint.

[tmonty12]

Remove this warning and its env-var constant. router_track_active_blocks is currently a no-op in SelectionService, but warning here does not improve the behavior. Follow up with a focused change that makes SelectionService honor it for both selection and booking, then the setting will work rather than merely warn.

[kangclzjc]

Removed in d9ba8e1, with the env const and its test. Making SelectionService honor router_track_active_blocks for selection and booking is a follow-up I'll file separately.

[tmonty12]

Remove this warning (and kv_aware_selection_enabled). Approximate mode in #13836 can perform prefix-aware selection with KV events disabled and positive overlap credit, so this message can incorrectly claim that prefill selects on load alone.

[kangclzjc]

Removed in d9ba8e1, with kv_aware_selection_enabled and its test. Agreed the premise breaks once #13836's approximate index lands; the prefill arm is now a no-op and prefill inherits the base config unchanged.

[tmonty12]

These are per-selection decode semantics, not static SelectionService configuration. Reuse the existing decode_router_config_override() in this package for overlap credit, KV-reuse assumption, and prefill-token tracking. Keep use_kv_events = false static because standalone decode has no event source, and retain the predicted-TTL clear because it requires events. With the request override, the related static/indexer clearing machinery should go away.

[kangclzjc]

Done in d9ba8e1. The decode arm keeps only use_kv_events = false and the predicted-TTL clear. Overlap credit, KV-reuse assumption and prefill-token tracking now come from decode_router_config_override() (made pub(crate) in epp.rs, wrapped by role_config::router_config_override_for_role). The router_prefill_load_model / serve_indexer clears only existed to satisfy cross-field validation of the static knobs and are gone; decode_inherits_prefill_load_model_and_serve_indexer_and_still_validates pins that a base setting both still yields a valid decode config.

[tmonty12]

Carry the existing decode RouterConfigOverride into this selector and supply it on decode selections and reservations; prefill should continue with no override. The current Selector::select_and_reserve always passes router_config_override: None, so the override needs to be retained on Selector (or passed with SelectRequest). This keeps standalone aligned with the integrated ext-proc router.

[kangclzjc]

Done in d9ba8e1. The override is retained on Selector (derived from its role in new_with_kv_router_config, so no call site changed) and select_and_reserve forwards it into the core request, which covers both the selection and the booking; prefill and aggregated forward None. pick() and SelectRequest are untouched. decode_selector_books_no_prefill_load_and_prefill_selector_books_it proves the forwarding end to end through the core: the same 16-token prompt books 16 prefill tokens on the prefill selector and 0 on decode (read back via SelectionService::loads).

[tmonty12]

Remove this guard and the separate topology parse. DYN_EPP_TOPOLOGY_MODE is standalone-only configuration, like the other standalone variables, so runtime mode should ignore it rather than fail. Remove the matching documentation and test that justify this special case.

[kangclzjc]

Removed in ce8631e — guard, separate topology parse, test and the docs sentence. Verified on the cluster that DYN_EPP_MODE=dynamo with DYN_EPP_TOPOLOGY_MODE=disaggregated set now starts normally and proceeds to Dynamo discovery.

[tmonty12]

Use nvidia.com/dynamo-worker-role as the default label key, with prefill and decode as the values. nvidia.com/role is too generic; retain DYN_EPP_WORKER_ROLE_LABEL for deployments that use the operator's component-type label.

[kangclzjc]

Done in 9114af8: default is nvidia.com/dynamo-worker-role, DYN_EPP_WORKER_ROLE_LABEL still overrides. One thing to flag rather than fix from this PR: DEP #11661 says nvidia.com/role in four places (the three "Deployable result" lines and the environment-contract row). Happy to send a DEP edit if you'd like it tracked there.

[tmonty12]

Please do not add per-role total-KV-block settings yet. Keep the shared DYN_EPP_TOTAL_KV_BLOCKS; this standalone role split has no consumer for distinct totals (conditional disaggregation is rejected). Per-role max_num_batched_tokens is needed because it drives scheduler capacity. Add per-role KV totals when the prefill/decode handoff or admission logic actually consumes them.

[kangclzjc]

Removed in ce8631e — DYN_EPP_{PREFILL,DECODE}_TOTAL_KV_BLOCKS fields, parse, accessor, docs rows and tests. The shared DYN_EPP_TOTAL_KV_BLOCKS stays; per-role max_num_batched_tokens stays since it drives scheduler capacity.

[tmonty12]

Move this warning to the highest standalone entrypoint, immediately after standalone mode and disaggregated topology are known, then return from that warning helper. It is a deployment-level limitation, not selector-construction state, and should be emitted once rather than whenever selectors are built.

[kangclzjc]

Moved in ce8631e to runner.rs, immediately after EppStandaloneConfig::from_env() — the first point where standalone mode and topology are both known — via a small helper that returns after logging. Emitted once per process; verified on the cluster it fires exactly once and before either selector is built. It no longer cites issue numbers; the docs note keeps the links.

[dynamo-ops]

/ok to test d169155

[kangclzjc]

Revision 2 — rebased, review feedback resolved, re-verified on a real cluster

Rebased onto main (absorbing SelectionServiceBuilder::new(config, WorkerType, registry),
peer_service → peer_replication, and the removal of the from_service entry points), then one
commit per review theme so each thread maps to a diff.

Thread → resolution

Thread	Commit	What changed
role_config.rs:111 decode semantics are per-selection, reuse decode_router_config_override()	d9ba8e139	Decode's overlap credit / KV-reuse / prefill-token tracking now ride on a per-request RouterConfigOverride produced by the existing epp.rs helper (made pub(crate)). Only use_kv_events=false and the predicted-TTL clear stay static. The router_prefill_load_model / serve_indexer clears existed only to satisfy cross-field validation of the static knobs and are gone; a test pins that a base setting both still yields a valid decode config.
epp_router.rs:115 carry the override into the selector, supply on selections and reservations	d9ba8e139	The override lives on Selector, derived from its role in the constructor, and select_and_reserve forwards it into the core request (which covers both the selection and the booking). Prefill and aggregated forward None. pick() and SelectRequest are untouched, so the wrong-override-on-wrong-selector mistake is not expressible. A behavioural test proves the forwarding: the same 16-token prompt books 16 prefill tokens on the prefill selector and 0 on decode (read back through SelectionService::loads).
role_config.rs:4 one-sentence module doc	d9ba8e139	Reduced to the one invariant the code cannot state: a decode worker never computed the prompt, so it is never credited for overlap or charged prefill work, and it has no event source. The "why two services" rationale now lives once, at build_selectors, and says what is still true after the override move: use_kv_events is fixed at construction and the catalogs must be disjoint.
role_config.rs:51 remove the router_track_active_blocks warning	d9ba8e139	Removed with its env const and test. Making SelectionService honor the flag is a follow-up.
role_config.rs:98 remove the KV-aware warning	d9ba8e139	Removed with kv_aware_selection_enabled and its test. Its premise (events off ⇒ load-only) stops holding once #13836's approximate index lands.
runner.rs:211 remove the runtime-mode guard	ce8631e51	Guard, separate topology parse, test and the docs sentence are gone; runtime mode ignores DYN_EPP_TOPOLOGY_MODE like the other standalone variables. Verified on the cluster: DYN_EPP_MODE=dynamo with DYN_EPP_TOPOLOGY_MODE=disaggregated set no longer fails startup.
epp_standalone_config.rs:186 no per-role total-KV-blocks yet	ce8631e51	DYN_EPP_{PREFILL,DECODE}_TOTAL_KV_BLOCKS removed (fields, parse, accessor, docs rows, tests). Shared DYN_EPP_TOTAL_KV_BLOCKS stays; per-role max_num_batched_tokens stays.
epp_router.rs:122 move the "incomplete" warning to the entry point	ce8631e51	Emitted once in runner.rs immediately after EppStandaloneConfig::from_env(), gated on the topology, via a small helper that returns after logging. It no longer cites issue numbers; the docs <Note> keeps the links.
worker_role.rs:27 default label nvidia.com/dynamo-worker-role	9114af884	Done; DYN_EPP_WORKER_ROLE_LABEL still overrides. DEP #11661 drift: the DEP text says nvidia.com/role in four places (lines 516, 531, 544, 610) — flagging rather than editing the DEP from this PR.
Summary: trim comments substantially	d169155fb	~78 added comment blocks → roughly a third kept. Rules applied: one home per fact (five facts were each stated 3–4×), no issue/plan/milestone references in code comments, no history narration or branch defence, and no "byte-identical to previous behaviour" claims — upstream had no worker-count logging, so that was only true against the PR's own first commit (dagil's note 2).
Summary: consolidate tests	d169155fb	199 → 161 test functions in the crate with the same assertions (upstream main has 142, so the PR now adds 18 instead of 61): the thirteen one-per-branch raw_worker_from_pod tests (seven upstream + six new) are one table, the label-key / topology-parse / per-role-capacity cases each fold into the file's existing Case-table shape, the three routing-invariant picks are one table over the shared fixture, and single-accessor tests became rows. Kept standalone: role flip, live label removal, the mutation-path count invariant, add/flip/remove reconciliation across two real selectors, and the cross-catalog leak checks.
dagil: KV-event port rows need the disaggregated qualifier	d169155fb	Both rows now say they apply to prefill workers only under disaggregated.
dagil: schedulable_count is a non-test pub fn	d169155fb	Gated #[cfg(test)] beside its sibling.

Real-cluster verification (revision 2)

Updated: the last four rows were run afterwards on the final head 121e15965, which also inlines the dependencies helper into from_selector.

Same rig as the PR body (throwaway k3s v1.34.2 in Docker, Gateway API v1.5.1 + GAIE v1.2.1 +
agentgateway v1.0.0 via install_gaie_crd_agentgateway.sh, echo workers, EPP on the host), now with
the workers labelled nvidia.com/dynamo-worker-role.

check	result
DYN_EPP_MODE=dynamo + DYN_EPP_TOPOLOGY_MODE=disaggregated (guard removed)	✅ starts, standalone=false, proceeds to Dynamo discovery; the topology setting is ignored, not rejected
disaggregated startup	✅ the "pair selection is not implemented yet" warning fires once, before either selector is built; then role=prefill / role=decode selectors, census prefill ready=2 / decode ready=2, ZMQ listeners on the two prefill IPs only
100 requests, destination cross-checked against the live label	✅ 44 → 10.42.0.8 decode, 56 → 10.42.0.9 decode, 0 prefill
decode scaled to 0 (pods confirmed deleted)	✅ 503 no decode workers available + Role has no ready workers … role="decode"
prefill pod flipped to decode	✅ becomes the serving worker (Hostname: vllm-prefill-…-gqv7c)
label removed / label encode	✅ 503 both; reason="role_label_missing" / reason="role_label_invalid" in the EPP log
aggregated parity (topology unset, same pool, same labels)	✅ role="aggregated" ready=4, 4 ZMQ listeners, all 4 pods serve (prefill- and decode-labelled alike), no census, no warning
follow-up on 121e15965: census, decode empty from process start	✅ Role has ready workers role="prefill" ready=2 then WARN … Role has no ready workers at startup … role="decode"
census, pool entirely empty from process start (index_changed never set)	✅ one startup WARN per role; request → 503 no decode workers available
reverse flip decode → prefill	✅ flipped pod got 0 of 30 requests and gained a ZMQ listener; the ReplicaSet's replacement decode pod served immediately
client forges x-gateway-destination-endpoint naming each prefill IP (3 tries, incl. the freshly flipped pod)	✅ all three landed on decode-role pods

# disaggregated startup, revision 2
WARN dynamo_ext_proc::runner: DYN_EPP_TOPOLOGY_MODE=disaggregated: prefill/decode pair selection is
     not implemented yet, so decode workers still perform the whole prefill
INFO dynamo_ext_proc::selector: Initialized in-process selection service replicated=false role=prefill
INFO dynamo_ext_proc::selector: Initialized in-process selection service replicated=false role=decode
INFO dynamo_ext_proc::pod_discovery: Role has ready workers role="prefill" ready=2
INFO dynamo_ext_proc::pod_discovery: Role has ready workers role="decode" ready=2
INFO ...indexer::listener: ZMQ listener starting worker_id=8586505338284351 endpoint="tcp://10.42.0.6:5557"
INFO ...indexer::listener: ZMQ listener starting worker_id=6483078548074001 endpoint="tcp://10.42.0.7:5557"

# runtime mode with the topology variable set: no longer an error
INFO dynamo_ext_proc::runner: Starting Dynamo Rust EPP port=9002 health_port=9003 namespace=dynamo component=backend standalone=false
INFO dynamo_ext_proc::runner: Initializing KV-aware router from discovery...

Stated limit: the RouterConfigOverride cannot be observed end-to-end in this rig. The echo
workers publish no KV events, so the prefill index is empty and effective_cached_blocks is 0 in
every mode regardless of the override. Forwarding is proven at the unit level (the 16-vs-0 booking
test above); the cluster run proves no regression in routing.

Status

cargo test -p dynamo-ext-proc: 161 passed. clippy -D warnings and fmt clean.

🤖 Generated with Claude Code

[dynamo-ops]

/ok to test 121e159

[dynamo-ops]

/ok to test 52cd9ee

[kangclzjc]

Rebased onto current main (a5b48b082, 91 commits) — no conflicts, all 8 commits re-signed; build, 162 tests, clippy -D warnings and fmt green on 52cd9eee9.

One interaction worth stating: #13669 (the standalone decode-sidecar contract, sibling #13405) landed in that range and added PickResult::selected_prefill_endpoint, which the server turns into the sidecar's prefill-endpoint header when Some. The standalone pick() builds PickResult with ..Default::default(), so under disaggregated it stays None: no prefill endpoint is advertised and the sidecar proxies straight to the decode worker. That is the intended state for this PR — choosing the prefill worker is #13407 — and it is the same fact the startup warning states.

🤖 Generated with Claude Code

[kangclzjc]

Real-cluster rerun on the rebased head 52cd9eee9 (main a5b48b082, incl. #13669)

Same rig as before (throwaway k3s in Docker, Gateway API v1.5.1 + GAIE v1.2.1 + agentgateway v1.0.0 via install_gaie_crd_agentgateway.sh, echo workers labelled nvidia.com/dynamo-worker-role, EPP on the host). Both topologies, plus the sidecar-contract header now that #13669 is in main. The echo worker reflects every request header it receives, so the header checks are observed at the backend, not inferred.

check	result
DYN_EPP_MODE=dynamo + DYN_EPP_TOPOLOGY_MODE=disaggregated	✅ starts, standalone=false, proceeds to discovery; not rejected
disagg startup, 2 prefill / 2 decode	✅ "pair selection not implemented" warning once, before either selector; role=prefill / role=decode selectors; census 2/2; ZMQ listeners on the two prefill IPs only
disagg 100 requests, destination vs live label	✅ 58 + 42 → decode, 0 prefill
disagg x-prefiller-host-port on the wire	✅ normal request: backend saw it 0 times (selected_prefill_endpoint is None, so the sidecar would proxy straight to decode); client-forged header: stripped, backend saw it 0 times, request still landed on decode
disagg decode scaled to 0	✅ 503 no decode workers available + zero-crossing warn
disagg prefill→decode flip / label removed / encode	✅ 200 on the flipped pod / 503 / 503, role_label_missing and role_label_invalid logged
disagg reverse flip decode→prefill	✅ flipped pod got 0 of 30, gained a ZMQ listener
disagg client forges x-gateway-destination-endpoint → each prefill IP	✅ all landed on decode
agg startup (topology unset, same pool, 3 prefill- + 2 decode-labelled pods after the flips)	✅ role="aggregated" ready=5, 5 ZMQ listeners, no census, no warning
agg 30 requests	✅ all 5 pods serve, both label values alike
agg x-prefiller-host-port on the wire	✅ absent on normal requests; client-forged header stripped

Rig torn down afterwards. The one limit stays as stated earlier: the per-request RouterConfigOverride is not observable in this rig (no KV events, empty index); it is covered by the 16-vs-0 booking test.

🤖 Generated with Claude Code

[dynamo-ops]

/ok to test fb91bf3

[kangclzjc]

Rebased onto current main (517572309, 347 commits). This one was not conflict-free: #14570 (unify frontend and standalone selection core) landed in the range and replaced the seam this PR sits on, so I squashed the reviewed revision-2 series into one commit (fb91bf396) and re-resolved once against the new shape rather than carrying 8 commits through 8 rounds of conflicts. The reviewed decisions are unchanged; what moved is the plumbing underneath them:

upstream change	how this PR now sits on it
Selector::reconcile / WorkerRegistration removed; membership flows through kv-router's CatalogReconciler over a WorkerCatalogSource	TopologyAdapter::spawn now creates one RoleReflectorSource + CatalogReconciler per role over the same PodDiscovery; each source snapshots ready_workers_for(role). Aggregated is one source with WorkerRole::Aggregated, i.e. the upstream path.
RawWorker.kv_events_endpoints became a per-DP-rank map (KvEventPorts)	RoleDiscoveryConfig carries KvEventPorts + replay port + optional role label; decode workers get an empty map and no replay endpoint, so data_parallel_size resolves to 1 and the worker stays schedulable under use_kv_events=false.
RenderClient enum (vLLM / SGLang renderer)	from_selector_parts takes RenderClient; the role split is renderer-agnostic.
SelectionServiceBuilder default factory + session_affinity	both preserved on every role's selector; only indexer_threads still differs by role.
TokenizerProtocol → RendererProtocol, DYN_EPP_DATA_PARALLEL_SIZE / _STRIDE config	for_test() and the docs table updated; the DP rows sit beside the topology rows.

Gates on fb91bf396: build, 178 tests (upstream main has 159, so the PR adds 19), clippy -D warnings, fmt, all green; commit is signed and GitHub-verified; mergeable. No test from the reviewed series was dropped — the three that disappeared from selector.rs are upstream's own removals of the old reconcile path.

One catch during the merge worth recording: git's 3-way merge of the config table silently dropped the DYN_EPP_TOPOLOGY_MODE / DYN_EPP_WORKER_ROLE_LABEL rows and the KV-event-port qualifiers (they were adjacent to the new DP rows). Caught by diffing the resolved file against the pre-rebase branch and restored; the same check on every Rust file found nothing missing.

🤖 Generated with Claude Code

[kangclzjc]

Real-cluster rerun on the rebased head fb91bf396 (main 517572309, over the #14570 seam)

Same rig as before (throwaway k3s in Docker, Gateway API v1.5.1 + GAIE v1.2.1 + agentgateway v1.0.0 via install_gaie_crd_agentgateway.sh, echo workers labelled nvidia.com/dynamo-worker-role, EPP on the host). This run matters more than the previous ones: the role split now rides on kv-router's CatalogReconciler (one per role over the same reflector) and the DP-aware RawWorker, neither of which existed when the earlier matrices ran.

check	result
DYN_EPP_MODE=dynamo + DYN_EPP_TOPOLOGY_MODE=disaggregated	✅ starts, standalone=false, proceeds to discovery; not rejected
disagg startup, 2 prefill / 2 decode	✅ "pair selection not implemented" once, before either selector; role=prefill / role=decode selectors; census 2/2; ZMQ listeners on the two prefill IPs only
disagg 100 requests vs live label	✅ 48 + 52 → decode, 0 prefill
disagg x-prefiller-host-port on the wire	✅ absent on normal requests; client-forged header stripped, still landed on decode
disagg decode scaled to 0	✅ 503 no decode workers available + zero-crossing warn
disagg prefill→decode flip / label removed / encode	✅ 200 on the flipped pod / 503 / 503, role_label_missing and role_label_invalid logged — i.e. the per-role CatalogReconcilers converge on live changes
disagg reverse flip decode→prefill	✅ flipped pod got 0 of 30, gained a ZMQ listener
disagg client forges x-gateway-destination-endpoint → each prefill IP	✅ all landed on decode
disagg census, decode empty from process start	✅ prefill ready=3 INFO + decode at startup WARN
disagg census, pool entirely empty (every pod deleted, incl. the ReplicaSet-orphaned relabelled one)	✅ one at startup WARN per role; request → 503
agg startup (topology unset; 3 prefill- + 2 decode-labelled pods after the flips)	✅ role="aggregated" ready=5, 5 ZMQ listeners, no census, no warning
agg 30 requests	✅ all 5 pods serve, both label values alike
agg x-prefiller-host-port on the wire	✅ absent normally; forged header stripped

Rig torn down afterwards. Same stated limit as before: the per-request RouterConfigOverride is not observable in this rig (no KV events, empty index); it is covered by the 16-vs-0 booking test.

🤖 Generated with Claude Code